Utility meters are devices the measure the consumption or flow of a commodity, such as gas, water or electricity. Traditionally, utility meters measured the consumption of a commodity by a facility, for example, a residence, factory, or commercial establishment. Other utility meters may measure the flow of a commodity out of a facility such as a power generation plant or a distribution network.
In general, however, utility meters measure commodity consumption and retain the commodity consumption data for use by the utility service provider. Commodity consumption data may include the quantity electrical energy consumed or the volume of gas or water consumed. The utility service provider uses the commodity consumption data to perform its billing function, among other things.
Many types of meters, including in particular electricity meters, employ electronic circuits to obtain and record consumption data. Electricity meters using such electronic circuits typically digital current and voltage signals, and then perform algebraic operations on the digitized signals to obtain energy consumption data. The energy consumption data is typically then displayed on a digital display.
Power for the electronic circuit is derived from the power lines being measured. As a result, no “external” source of power is necessary. Moreover, in the event of a power interruption, the resultant lack of power to the electronic circuit is inconsequential because there typically is no power consumption to measure. Accordingly, the model of an electricity meter that employs electronic measurement circuits that are powered by the mains power lines has been widely adopted.
One advantage of the use of electronic meters is that higher level data processing functions may be readily incorporated into the meter. For example, a single meter platform may readily be adapted to perform time-of-use metering, demand metering, or other types of metering with a simple software adjustment. Moreover, a single meter platform may readily be adapted for installation into various types of electrical wiring configurations (three wire delta, four wire delta, three wire wye and four wire wye) through the use of software changes.
To this end, meters typically include the facility to receive meter program data (e.g. program parameters) externally after the manufacture of the meter. For example, many meters include optical port through which meter parameters and meter calibration data may be externally loaded into the meter. In such meters, a non-volatile memory such as an electrically erasable programmable read-only memory (“EEPROM”) is used to store the programmed values. Non-volatile memory is employed to ensure that the programmed data remains within the meter after power is removed from the meter for shipment to the customer.
The advantage of using adjustable program parameters stored in EEPROM in the meter is that the manufacturer may produce a single meter that is adaptable to large numbers of various customer configurations. As a result, large numbers of different meters need not be inventoried. Instead, one type of meter is inventoried, and then may be programmed to suit customer orders as they are received.
While the above-described process facilitates configuration of many meter features and operations after manufacture of the meter is substantially complete, it nevertheless requires significant time and equipment. In particular, storing operational parameters into the meter requires that electrical power be available in the meter in order to carry out the programming task. Thus, for example, if several meters must be “programmed” to fulfill a specific customer request, all of the meters must be connected to electrical power as well as to the programming device.
Accordingly, there is a need for a method and apparatus that further facilitates configuration of a meter that requires a reduced amount of time and equipment. Such a method and apparatus would ultimately provide greater flexibility and/or less cost in configuring meters for different applications.